Arisaka Defense Tailcap Adapter — Streamlight ProTac HL-X

The Arisaka Defense Tailcap Adapter lets Streamlight ProTac Rail Mount HL-X lights accept Surefire-style tailcaps and remote switches, restoring compatibility with commonly used remote-switch assemblies. It requires the use of a Surefire UE or DS tailcap (not included) and supports remote switches such as the Surefire SR-D-IT and TNVC/Unity TAPS. This adapter is not compatible with the Protac 2.0 Rail Mount lights or the Rail Mount HL-X Laser model. The kit includes two o-rings—one sized for CR123 cells and one for 18650 cells—to help prevent battery rearward movement under recoil.

Key Specifications

• The color is Black.
• This item is classified as a Part.
• It fits Streamlight ProTac lights.
• The model designation is Tailcap Adapter.
• The finish is Anodized.
• Requires a Surefire UE or DS tailcap to function (tailcap not included).
• Includes two o-rings—one sized for CR123 cells and one for 18650 cells—to stabilize the battery.
• Not compatible with Protac 2.0 Rail Mount lights.
• Not compatible with the Rail Mount HL-X Laser model.
• Enables use of Surefire SR-D-IT and TNVC/Unity TAPS remote switches.

Whether you’re integrating a HL-X into an existing remote-switch setup or adapting components across platforms, this adapter provides a compact, practical solution to restore Surefire-style tailcap compatibility and reduce battery movement. It’s a straightforward way to maintain modularity and reliable function when using compatible Streamlight HL-X lights with Surefire-style tailcaps and remote switches.